1. Field of the Invention
The present invention relates generally to formulations that can be taken as dietary supplements, and more particularly, to a specific thymoquinone containing extract of Nigella sativa seed and cranberry fruit extract or methionine to address general physiological stress as well as inflammation and microbial infections of the female urinary tract.
2. Description of the Related Art
Reoccurring cystitis or urologic syndrome generally manifests a combination of symptoms including irrative voiding, hematuria or inappropriate urination. Often seen in females of nearly all species, the most common form is termed idiopathic lower urinary tract disease or idiopathic cystitis. Other forms of urologic syndrome include urolithiasis, urinary tract infections and, least common, anatomic deficits (FIG. 1).
Research indicates that nitric oxide (NO) plays an important role in the pathogenesis of cyclophosphamide-induced cystitis in rats, and some factors may be released in cyclophosphamide-treated rat plasma that stimulate iNOS (inducible nitric oxide synthase) expression in primary culture of rat bladder smooth muscle cells [Xu X, Cubeddu L X, Malave A. Expression of inducible nitric oxide synthase in primary culture of rat bladder smooth muscle cells by plasma from cyclophosphamide-treated rats. Eur J Pharmacol. Mar. 23, 2001; 416(1-2):1-9]. Alterations in NO levels have been demonstrated in some humans with interstitial cystitis as well as in chemically induced animal models of cystitis [Koskela L R, Thiel T, Ehren I, De Verdier P J, Wiklund N P. Localization and expression of inducible nitric oxide synthase in biopsies from patients with interstitial cystitis. J Urol. August 2008; 180(2):737-741. Wilkinson D R, Erickson A D. Urinary and Serologic Markers forInterstitial Cystitis: An Update. Curr Urol Rep. September 2006; 7(5):414-422]. A significant increase in baseline NO production in cats with feline interstitial cystitis compared with that in healthy cats has been found in smooth muscle and mucosal strips. It has been shown that the barrier property of the urothelial surface is disrupted in feline interstitial cystitis and iNOS mediated increase in NO alters barrier function in other types of epithelium. Additionally, iNOS dependent NO production may have a role in epithelial barrier dysfunction in feline interstitial cystitis [Birder L A, Wolf-Johnston A, Buffington C A, Roppolo J R, de Groat W C, Kanai A J. Altered inducible nitric oxide synthase expression and nitric oxide production in the bladder of cats with feline interstitial cystitis. J Urol. February 2005; 173(2):625-629]. Therefore, inhibitors of iNOS may be useful agents in the treatment of interstitial cystitis.
There appears to be no single, primary causative agent associated with idiopathic cystitis. Among the risk factors identified, stress and a urinary pH greater than 7.0 are most frequently reported. While bacterial infection seems to play a primary role in the disease, several research groups have proposed that viral infections may have a predisposing influence. Low fuid intake is also considered a significant risk factor for recurrent idiopathic cystitis.
Oral medications that may improve the signs and symptoms of interstitial cystitis include ibuprofen and other nonsteroidal pain medications to relieve discomfort. Antibiotics, steroids, diet change, and/or increased water intake are the commonly prescribed treatments. But treatment of idiopathic cystitis with presently available formulations has drawbacks. For example, reduction of stress is considered critical to terminating the cycle of recurrence. Treatment with amitriptyline, one of the early tricyclic antidepressants, has been reported to be highly effective in reducing the frequency of episodes in severe recurrent cases of idiopathic cystitis. However, potential side-effects of amitriptyline include sedation, hypotension, and weight gain.
Moreover, episodes of idiopathic cystitis tend to be self-limiting and resolve within ten days regardless of the treatment, but if the risk factors for idiopathic cystitis are not addressed, the likelihood of recurrence is high. And a frequent complication in active untreated cystitis includes increased risk of infection, often leading to inflammation and painful urination.
Research suggests that acidifying the urine may be effective in the management of recurrent idiopathis cyctitis. Ingestion of cranberry fruit juice and methionine are speculated to help provide such acidification. One double-blind, placebo-controlled study of 153 elderly women indicated that the consumption of 300 mL of commercially available standard cranberry juice reduced the odds of bacteriuria by forty-two percent [Avorn et al., Reduction of bacteriuria and pyuria after ingestion of cranberry juice, 271 JAMA 751-754 (1994)]. Other studies suggest that cranberry juice may be more effective in treating than in preventing bacteriuria and urinary tract infections [Fleet, J. C. New support for a folk remedy: cranberry juice reduces bacteriuria and pyuria in elderly women, 52 NUTR. REC. 168-170 (1994)]. However, it is unclear whether the positive results obtained with cranberry fruit juice are due to some ingredient of cranberries, such as quinic acid, which is thought to have an antimicrobial role, or whether any observed positive results are due simply to the consumption of additional fluids.
While ingestion of cranberry fruit juice is thought to be useful for alleviating urinary cystitis, the efficacy of a cranberry fruit extract for the same application has not been demonstrated. Publications relating to the efficacy of cranberry fruit and cystitis report on the use of cranberry fruit juice and not on cranberry fruit extracts. Moreover, any positive clinical results obtained with cranberry fruit juice may simply be due to the consumption of additional fluids, a practice known to reduce the risk of urinary tract infections.
Today, cranberry fruit extract is widely available in America and European countries as a dietary supplement in the form of tablets, capsules or gel caps. Examples of available cranberry fruit extract products include the following trade designations, with the milligrams of extract in a dose indicated parenthetically if known: HealthCare Cranberry Fruit (475 mg capsules, 2 to 4 capsules three times daily) and YourLife Cranberry (300 mg caplets, 2 caplets three times daily).
However, while the historical and clinical use of cranberry fruit juice may indicate that cranberries are useful for treating urinary tract infections, cranberry fruit extract has not been optimally formulated into a dietary supplement that can effectively relieve all the symptoms of recurrent idiopathic cystitis [Jepson R G, Craig J C. Cranberries for preventing urinary tract infections. Cochrane Database Syst Rev. 2008(1):CD001321].
An ideal formulation for the reduction of risk factors associated with cystitis would (i) decrease urinary pH, (ii) reduce physiological stress, (iii) reduce pain, and (iv) decrease the inflammatory response by inhibiting iNOS-mediated NO production. Such a formulation should therefore enhance potential acidification properties offered by cranberry fruit and address the additional risk factors of physiological stress, inflammation and infection. It should be inexpensively manufactured and comply with all governmental regulations. While it may provide one or two of these features, cranberry juice and cranberry extracts cannot provide all of these desirable features. Therefore, a formulation containing cranberry juice, cranberry extracts or any of its active ingredients with other beneficial ingredients would be an improvement over those presently commercially available.
Methionine is an amino acid that may help acidify urine and doses are available commercially in amounts ranging from 200 to 600 mg. Methionine has been used clinically to acidify the urine. Doses of 1500 to 3000 mg/day in humans reduced the mean pH values of the urine of 19 subjects from 7.5 to 5.5 [Jarrar, K., R. H. et al., Struvite stones: long term follow-up under metaphylaxis, 30 ANN UROL. (Paris) 112-117 (1996)].
Nigella sativa, commonly known as black seed or black curcumin, is traditionally used in the Indian subcontinent, Arabian countries, and Europe for culinary and medicinal purposes as a natural remedy for a number of illnesses and conditions that include asthma, hypertension, diabetes, inflammation, cough, bronchitis, headache, eczema, fever, dizziness and influenza. Much of the biological activity of the seeds has been shown to be due to thymoquinone, the major component of the essential oil, but which is also present in the fixed oil.
The seeds of N. sativa as well as thymoquinone are characterized by a very low degree of toxicity. Administration of either the seed extract or its oil has been shown not to induce significant adverse effects on liver or kidney functions even at extremely high doses [Ali B H, Blunden G. 2003. Pharmacological and toxicological properties of Nigella sativa. Phytother Res 17: 299-305]. Thus, thymoquinone possesses the necessary safety factor for commercialization in the dietary supplement market.
As seen in Table 1, thymoquinone content of the essential (volatile) oil fraction is roughly 27-57 percent. The essential oil fraction, however, constitutes only one percent of the seed oils. Thus, thymoquinone comprises only about 0.3 to 0.6% of the fixed oil fraction, the most common commercially available product of N. sativa. 
Traditional solvent extraction is time-consuming, requires multiple steps, and consumes large amounts of organic solvents. The amount and the price of organic solvent directly influences the total cost of producing an acceptable extract or product. Moreover, when the final product is used as a food ingredient, it is absolutely necessary to remove all potentially toxic solvents.
TABLE 1Thymoquinone content of various oil fractions of N. sativa seedsCONTENTFRACTIONCOMPONENT[% w/w]SeedsFixed oils.36Fixed oil (cold pressed)Fatty acids, protein,58thiamin, ribovflavin, pyridoxine,niacin, folic acid, and calcium.Essential fattyMyristic acid (C14)0.5acids in fixed oilPalmitic acid (C16)13.7Palmitoleic acid (C16 w-9)0.1Stearic acid (C18)2.6Linoleic acid (C18 w-6)57.9Linolenic acid (C18 w-3)0.2Arachidic acid (C201.3Essential oil0.5-1.5Essential oil (volatile oil)Thymoquinone27-57p-Cymene 7.1-15.5Carvacrol 5.8-11.6trans-Anethole0.25-2.3 p-terpineol2.0-6.6longifoline1.0-8.0
Supercritical fluid extraction (SFE) has already proven itself as an attractive technique for selectively removing compounds from complex food matrices. Specifically SFE offers the possibility of mild extraction conditions combined with low energy requirements for solvent recovery. The high selectivity of the extraction process and the reduced potential for oxidation of the extracted materials make this technique especially suitable for extractive isolation of natural products. The lone drawback to SFE is the high capital cost of the extraction set-up.
A novel, supercritical CO2 extract of N. sativa has is described that contains 2.0 to 6.0% (w/w) thymoquinone, an amount between that of the fixed and essential oils, and exhibits anti-inflammatory activity in excess of its thymoquinone content alone. This novel thymoquinone composition may also be obtained commercially from Garden State Nutritionals, 8 Henderson Drive, West Caldwell N.J.
However, thymoquinone has not been optimally formulated into compositions that can reduce all of risk factors associated with cystitis and thereby: (i) decrease urinary pH, (ii) reduce physiological stress, (iii) reduce pain, and (iv) decrease the inflammatory response. Therefore, a formulation containing thymoquinone and cranberry juice, cranberry extracts or any of the active ingredients of cranberry fruit, with the other beneficial ingredients contemplated by the present invention, would be an improvement over formulations that are presently commercially available.